The present invention relates generally to the provision of xe2x80x9cblendsxe2x80x9d from a first data value to a second data value and, in particular, to methods and apparatuses for the creation of complex blends within images in computer graphic imaging systems.
In modern computer graphic imaging systems, it is often necessary to create blends of color or opacity. The color or opacity data at a first data point takes on a first value and at a second data point takes on a second value, with the data points between the first data value and the second data value having an aesthetically pleasing monotonically increasing or decreasing series between the first data value and second data value.
With the increasing levels of computer power available to the general public in the form of desk top workstations and personal computers, there has come an increasing level of complexity in the application programs available for the creation of complex computer graphical images. Hence, products such as Adobe""s Photo shop and Illustrator (trade mark) and Quark""s Express (trade mark), allow, through a process of interactive editing, the creation of complex images. These images can be of great complexity and can comprise a number of overlapping layers with differing layers possibly having various degrees of transparency.
With the need to create complex and striking images, there is also the need to create such images rapidly and inexpensively. Further, there is a general need to be able to create complex computer graphical objects having slowly varying blends of an extremely complex nature.
It is an object of the present invention to provide a method and apparatus for the creation of complex blends of data.
In accordance with a first aspect of the present invention, there is provided a method of creating a blend from one arbitrary edge to a second arbitrary edge in a computer graphic image creation system, the method comprising the steps of:
determining a color along each of the edges;
forming a parametric equation for a color of each pixel within the area bounded by the edges; and
solving the parametric equation to derive a color for each of the pixels.
In accordance with a second aspect of the present invention, there is provided a method of creating a blend from a first arbitrary edge to a second arbitrary edge in a computer graphic image creation system, the method comprising the steps of:
determining a color along each of the edges;
vectorising each of the edges into corresponding line segments;
matching pairs of the line segments from each of the edges so as to form polygons having a defined color at their vertices; and
determining a color for each pixel of the polygon from the defined color of the vertices.
Preferably, the matching step further comprises matching pairs of line segments in accordance with their relative distance along each of the edges. Alternatively, the matching step further comprises matching pairs of line segments in accordance with their parametric distance along each of the edges.
In accordance with a third aspect of the present invention there is provided an apparatus for creating a blend from one arbitrary edge to a second arbitrary edge in a computer graphic image creation system, the apparatus comprising:
edge color determination means for determining a color along each of the edges;
parametric determination means for forming a parametric equation for a color of each pixel within the area bounded by the edges coupled to the edge determination means; and
pixel color deriving means for solving the parametric equation to derive a color for each of the pixels coupled to the parametric determination means.
In accordance with a fourth aspect of the present invention there is provided an apparatus for creating a blend from a first arbitrary edge to a second arbitrary edge in a computer graphic image creation system, the apparatus comprising:
edge color determination means for determining a color along each of the edges;
edge vectorising means for vectorising each of the edges into corresponding line segments coupled to the edge color determination means;
segment pair matching means for matching pairs of the line segments from each of the edges so as to form polygons having a defined color at their vertices coupled to the edge vectorising means; and
pixel color determination means for determining a color for each pixel of the polygon from the defined color of the vertices coupled to the segment pair matching means.
In accordance with a fifth aspect of the present invention there is provided a method of constructing computer graphical objects, the method comprising the steps of:
providing a plurality of interactively editable splines;
defining each of the splines to have a corresponding spline color;
creating a blend between pairs of the splines, the blend being substantially from the spline color of a first member of the pair to the spline color of a second member of the pair.
In accordance with a sixth aspect of the present invention there is provided a method of constructing computer graphical objects, the method comprising the steps of:
providing a plurality of interactively editable splines;
defining each of the splines to have a corresponding spline color; and
creating a blend between pairs of the splines further comprising the steps of:
determining a color along each of the splines;
forming a parametric equation for a color of each pixel within the area bounded by the splines; and
solving the parametric equation to derive a color for each of the pixels.
Typically, the spline color includes an associated opacity and the degree of opacity can take on values from fully opaque to fully transparent. Preferably the associated opacity includes a blend of degree of opacity being substantially from the opacity associated with the spline color of the first member of the pair to the opacity associated with the spline color of the second member of said pair.
In accordance with a seventh aspect of the present invention there is provided a method of constructing computer graphical objects, the method comprising the steps of:
providing a plurality of interactively editable splines;
defining each of the splines to have a corresponding spline color; and
creating a blend between pairs of the splines further comprising the steps of:
determining the color along each of the splines;
vectorising each of the splines into corresponding line segments;
matching pairs of the line segments from each of the splines so as to form polygons having a defined color at their vertices; and
determining a color for each of the polygon from the defined color of the vertices.
In accordance with a eighth aspect of the present invention there is provided an apparatus for constructing computer graphical objects comprising:
interactive editable spline generation means for providing a plurality of interactively editable splines;
spline color defining means for defining each of the splines to have a corresponding spline color coupled to the interactive editable spline generation means; and
spline pair blend creation means for creating a blend between pairs of the splines coupled to the spline color defining means, wherein a blend is created being substantially from the spline color of a first member of the pair to the spline color of a second member of the pair.